In an intense TV interview Thursday night, Fox News host and commentator Tucker Carlson promised Stormy Daniels' attorney Michael Avenatti that he would not use his inflammatory nickname for the lawyer on his show - then immediately went to a chyron that read: "CREEPY PORN LAWYER TOYING WITH 2020 RUN."

Carlson introduced Avenatti on "Tucker Carlson Tonight," explaining that in the past, Avenatti has "demanded that we stop referring to him by a certain, unflattering nickname."

"We haven't agreed to that demand, but tonight, as a gesture of goodwill, we will not use that nickname," Carlson vowed. "Because we're always grateful when guests are brave enough to show up in person, including in this case."

He then turned to the attorney.

"We could sit here and hurl insults at each other for the segment. Already done that," Carlson told Avenatti. "I've certainly insulted you. You've insulted me. But you seem smart, so let me take you seriously as somebody who wants to be involved in the public conversation."

At the time, the caption on the screen: "STORMY DANIELS' LAWYER IS HERE TONIGHT."

But once Carlson began questioning Avenatti about his presidential aspirations, it changed to include the nickname.

First it read: "CREEPY PORN LAWYER TOYING WITH 2020 RUN"

Then: "DOES AMERICA WANT CREEPY PORN LAWYER AS PRES?"

Then: "STORMY'S LAWYER AS CREEPY PORN PRESIDENT?"

Then: "TUCKER TAKES ON CREEPY PORN LAWYER"

Then just: "CPL FINALLY AGREES TO INTERVIEW WITH TUCKER"

Following the interview, Avenatti went on Twitter, calling Carlson a liar and criticizing Fox News for what happened.

"After he told me that he was not going to engage in 'name calling.' This is why so many people correctly conclude that @TuckerCarlson is a liar, just like Trump," Avenatti wrote late Thursday night.

"The extent there was any doubt as to the lack of professionalism of @TuckerCarlson or @FoxNews before tonight, there is no longer," the attorney wrote in a subsequent tweet. "What happened with the chyron tonight was a disgrace. Complete garbage - trash television. A new low."

Fox News did not immediately respond to a request for comment from The Washington Post.

At the start of the interview, Carlson admitted that he has been taking shots at Avenatti for months.

"I said I'd give you a fair interview," Carlson told Avenatti. "I actually don't have any interest in squabbling with you at all or name-calling - I've done a lot of that to you and you've done it to me."

"But not to my face," Avenatti interjected.

"I could, but what's the point?" Carlson continued. "I want to take you seriously. I'm serious."

First, the conversation turned to politics - namely Russia and its interference in the 2016 presidential election. Carlson said that Avenatti was using "reckless rhetoric" by accusing Russians of interfering in the election - a conclusion shared by the U.S. intelligence community and even Vice President Mike Pence.

"I think, under the circumstances, I stand by my words," Avenatti replied, "and I think for you to lecture me about reckless rhetoric is rather ironic in light of some of the reckless rhetoric that you engage in each and every day on this show."

Then the topic turned to Stormy Daniels.

"Let me ask you a question," Avenatti told Carlson. "Why is it that you don't call Donald Trump 'the creepy porn president?' He's the one that had sex with a 4-month-old son at home with my client without a condom. But you don't want to acknowledge that. Acknowledge it. Do you believe he had sex with my client?"

"Yes, I do," Carlson responded. "I've said that on the air multiple times."

The two then argued about whether Trump had a moral obligation to disclose the alleged sexual relationship, whether Avenatti is exploiting his client and whether Carlson is disrespecting them.

"Why don't you show some respect to my client and me and stop calling us 'a porn star' and 'a creepy porn lawyer?'" Avenatti said: "Do you have that big a problem with porn?"

To that, Carlson replied: "You're a little creepier even than I realized."